Fungal-infections have become the major cause for the high incidence and mortality in immunodeficiency patients. During the past 20 years, the incidence of mycotic infection has increased significantly. The high-risk population for the fungal-infection includes critical patients, surgical patients and the patients with HIV-infection, leukemia as well as other tumors. Additionally, the organ transplant recipients are also the high-risk population for fungal-infection.
The echinocandins are novel anti-fungal medicaments, which are effective in treating Candida- or aspergillus-infections, and the examples of which are Caspofungin and Micafungin. The echinocandins inhibit the fungi by inhibiting the formation of 1,3-β glucosidic bond, thereby reducing the toxicity toward the human and the side effects, while maintaining high efficiency. Therefore, compared with the traditional antifungal-medicaments, the echinocandins are safer when they are used.
FK463 (Micafungin) is the compound of Formula III, which is obtained by cutting the side-chain of compound FR901379 of Formula II (M0), thus forming compound FR179642 (M1) of Formula I, and adding the side-chain to compound of Formula I by synthesis. Therefore, the compound of Formula I with high-purity is very important for obtaining Micafungin with high-purity.

The following strains have been reported for transforming the compound of Formula II into the compound of Formula I by deacylating the acyl side-chain of the former compound: Streptomyces, such as Streptomyces anulatus No. 4811, Streptomyces anulatus No. 8703, Streptomyces sp. No. 6907, and IFO13244, IFO6798, IFO31963, IFO9951, NRRL12052, etc. U.S. Pat. No. 5,376,634 has disclosed a method for purifying the compound of Formula I, wherein, the method comprises the following steps: the compound of Formula II is transformed into the compound of Formula I by enzyme reaction, the transforming liquid is filtered, the compound of Formula I is purified through active coal column and silica gel column in turn, and upon concentration under reduced pressure, the compound of Formula I is obtained in white solid. For this method, the amount of the used organic solvent is great, and the used active coal and silica gel can not be recycled, therefore, such method will pollute the environment, be harmful to the physical healthy of the operators, and not suitable for large-scale production.
Therefore, it is urgent in the art to find a purification method without using great amount of solvent or silica gel, and such method can not only overcome the defects in the prior art, but improve the purity of the compound of Formula I.